Intravenous tubes have been widely used for supplying nutrients and medication to patients. Most existing, manually adjustable, clamps for regulating the flow rate through an intravenous tube have a high degree of inaccuracy, particularly after the clamped tubing has been in use for a period of time in excess of one hour. In addition, existing manually actuated clamps cannot be used where the fluid being delivered through the tubing is viscous, for example, blood. If a substantial degree of accuracy in flow rate maintenance is required, it has been necessary to utilize an expensive electric pump system. Even pump systems are limited in their accuracy. Additionally, in the event of power outage, electric pump systems would be useless.
A particularly common kind of flow regulator in medical applications is the so-called Adelberg clamp which uses the combination of an inclined plane or V-grooved surface and a roller that is moved along the inclined plane or grooved surface to variably compress the tube to allow more or less liquid to flow through the tube. Although widely used, the Adelberg clamp is less than ideally accurate and reliable, so as to require continual monitoring and adjustment to maintain a desired flow rate. The position of the roller is easily shifted in the V-grooved and ramped versions since the clamp design has not taken into consideration the direct effect of stress and strain as a critical contributing factor in maintaining an accurate and consistent flow rate through the roller clamp.